Dilution effect could refer to: Herd#Dilution effect, a survival strategy used by herds Heuristic (psychology)#Dilution effect, a psychological effect where irrelevant information weakens the effect of a stereotype Lethal injection#Dilution effect, an argument for opposing lethal injections Lyme disease#The dilution effect, a hypothesis that predicts that an increase in host biodiversity will result in a decrease in the number of vectors infected with a baterial species